Improvement in district-telegraph signal-boxes



L. B. FIRMAN.

DISTRICT TELEGRAPH SIGNAL-BOX.

Patented July 3,1877.

MMI'

N FETERS, PHOTD UTHOGRAPH WASHINGTOY D C 2 Sheets-Sheet 1.

I SW r'fmw lnuniur y2'Sl'leets-Sheet 2. L B. FIRMAN.

. DISTRICT TELEGRAPH SIGNAL-BOX.V No. 192,644, Patented July 3,1877.

NGA- v N,FETERs. PHOTD-LITHOGRAPHER, WASHINGTON. D C.

LEROY B. FIRMAN, OF CHICAGO, ILLINOIS.'

II'VIPRQV'EMENW IN `DlSTRlCyT-TELEGRAFIH SIGNAL-BOXES. v n

Speciiication formingV part of Letters Patent N o. .19 2,644, dated July3, 1877 application filed April 13, 1877.

To all 'whom fz't may concern:

Be it known that I, LEROY B. FIRMAN, of Chicago, in .thel county of Cookand State of Illinois,v have inven ted certain Improvements in AutomaticSignaling' Vpparatus, lof which the following is a specification In theaccompanying drawings, which form a part of this specification, Figure 1is a face view of the instrument, showing the dial and pointer. Fig. Zisthe view with the dial removed, bringing into sight a face view of themechanism. Fig. 3 is a side view of the exterior of the apparatus; andFig. 4 is a side view of the internal mechanism, the casing or exteriorboxing being shown in section.

Similar letters of reference made use of in the several figures denotelike parts wherever employed.

The apparatus is primarily designed to be used as one of a series ofsimilar machines, distributed among numerous stations, all of whichcommunicate with a central oce, constituting' a system such as is now inuse in many cities, and known as the district-telegraph system.7 Eachstation is designated by a number, and the apparatus is constructed towrite that number as a call, and subsequently to write any one ofseveral signals, at the will of the operator.

In the drawing, A is the casing which incloses the mechanism. It isprovided in front with a glass, and a dial, B, which latter is dividedinto a number of spaces, b, each of which denotes a different signalthat may be sent to follow the call by setting the pointer G at the onedesired, and thereafter pulling down the lever D, which winds up aspring, the recoil of which drives the train of clockwork by which themechanism is operated,

and at the same time returns the lever D to its first position.v

With regard to the train of gear-wheels or clock-work wound up and setin motion as above suggested, I have only to say that it is similar tosuch mechanism as is generally employed in like places, and shallconsider that the drawing is a sufficient description thereof.

The said clock-work drives a shaft, E, in the direction indicated by thearrow. This shaft carries the wheel F, upon the periphery of which isformed the teeth e, arranged in groups shuntcircuit, H, is provided, andwhich isl kept closed at the spring-key h by the pressure of the arm Jborne upon the same shaft Aas the lever D. When the lever is pulled downto start the mechanism this arm moves down with it, and, releasing itspressure upon the springkey,breaks the shunt-circuit and puts theinstrument in the line. This arm J serves also another purpose. Itslower part, below the shaft, extends down into a position to encounter apin, z', upon the call-writing wheel F, serving to stop said wheel at acertain point. The operation is, brieiiy, as follows: The lever D ispulled down and the spring thereby wound up. This motion breaks theshunt-circuit, and by freeing the stop allows the call-writing wheel torevolve, impelled by the spring, which also returns the lever D again toits former position, which is reached in time to stop the wheel andclose the shuntcircuit after a single revolution.

Upon the same shaft as' said call-writing wheel is a segment, K, and asimilar segment, K', upon the shaft which carries the pointer C isarranged to be engaged thereby upon occasion.

Upon the shaft carrying the pointer and the second segment is a wheel,L, cut with a number of equal-spaced teeth, Z, which are engaged by aspring-key, G', so that each tooth in passing breaks the circuit at g.

ln the drawing, the pointer C is shown as being set at the signalMessenger,7 and it will be seen that the segment K would not engage thesegment K at this position, and that consequently the call would be sentwithout any signal following. It is understood that the callunaccompanied by other signal demands a messenger. N ow, if the pointershall be set at the next signal, W S, the segment K will be turned sothat it will be engaged momentarily long enough to cause one tooth l topass beneath the spring-key G', causing one break in the circuit. So onfor each space described my invention, I

Wheel constructed to give the call or number of the station, and anotheradjustable wheel, which stands still While the call is being Written,and is engaged by the mechanism after the call has been sent, and iscaused to turn through whatever space or number of teeth desired bysetting the pointer, substantially as speciied.

2. The combination oi' the call-Writing wheel, upon the shaft of whichis a cogged segment, and the signal-Writing Wheel, uponV the shaft ot'which is another cogged segment, substantially as specified.

3. The signal-wheel, the dial, the pointer, the call-Wheel, and gearing'for operating the signal after the call is sent, combined, substantiallyas specified.

4. The signal-wheel, the call-Wheel, and

mechanism for operating the same in the man- A ner described, combinedwith the circuit, the spring contact-fingers, and the automatic shunt,substantially as set forth.

5. The combination, With a call-writing Wheel, of a signal-Writingwheehmoved by the same power, when the latter is provided with a numberof equal-spaced teeth, which write the signal desired by making acertain number of equal-spaced impulses, substanltially as specified.

L. B. FIRMAN.

Witnesses:

'JOHN W. MUNDAY, EDW. S. Evnnfrs.

